Which cookie is the Google's Two-Factor Authentication related cookie?

Question

Every time I start up my browser (palemoon [i.e., firefox]) I have to use the two-factor auth to log in.

I figure this is due to the fact that I have the browser clear cookies on exit, which I want, especially as Google floods my browser with cookies, that majority I don't think are needed the next time I fire-up my browser except the one related to authentication.

When I am looking at them (using cookie manager addon) I can only sometimes get a vague idea of what they are for (e.g., one is named gchat, it seems self-evident).

How can I figure out which one is the one that is related to authentication, so I can make an exception/keep that one and then continue to nuke the others on exit?

P.S. How much tracking info is gleaned from that authentication cookie? Anyone know?

Answer 1

Google has a support page about this feature, but their advice is simply to enable every cookie matching [*.]google.com so they won't tell you which exact cookies you really need for this exact functionality.

There is no good way to find out the answer to your question, if Google won't answer it, the best we can do is guess and experiment. Keep one cookie, see if it worked. If not, try another one. It could even require several cookies together, so try combinations. And then hope that Google doesn't decide to change things in the future once you figure it out!

P.S. Cookies generally allow a site to track your browser from session to session, but since you're logging in to Google, they already are tracking your activity. What do you hope to accomplish by dumping the cookies?